Self-assembly of hemin on carbon nanotube as highly active peroxidase mimetic and its application for biosensing

Hemin was assembled on the surface of single-walled carbon nanotubes (SWCNT) through non-covalent functionalization by p-p stacking. The resulting nanohybrid of hemin-SWCNT possessed an intrinsic peroxidase-like activity, and could effectively catalyze oxidation of the substrate 3,3,5,5-tetramethylbenzidine by H2O2 to develop a blue color in aqueous solution. The activity of hemin-SWCNT hybrid material was much higher than the activity of hemin alone. Combination of the catalytic reaction of glucose with glucose oxidase and the hemin-SWCNT hybrid catalytic reaction, a colorimetric method for glucose detection was also developed. The hemin-SWCNT nanohybrid also exhibited high stability and excellent reusability.